The present invention relates generally to the field of disc drive storage devices. More particularly, the present invention relates to the monitoring of the temperature of the disc drive.
Hard disc drives enable users of computer systems to store and retrieve vast amounts of data in a fast and efficient manner. In a typical disc drive, the data are magnetically stored on one or more discs which are rotated at a constant high speed and accessed by a rotary actuator assembly having a plurality of read/write heads that fly adjacent the surfaces of the discs.
The position of the heads is controlled by a closed loop, digital servo circuit. A preamp and driver circuit generates write currents that are used by the head to magnetize the disc during a write operation and amplifies read signals detected by the head during a read operation. A read/write channel and interface circuit is operably connected to the preamp and driver circuit to transfer the data between the discs and a host computer in which the disc drive is mounted.
Disc drive manufacturers typically produce a large number of nominally identical drives which are individually optimized during the manufacturing process through the setting of parameters that affect the operation of various disc drive circuits, such as the preamp and driver circuit, the servo circuit and the read/write channel. Such parameters are well known and typically include write current, write precompensation, servo gain, data and servo level detection thresholds, transversal equalizer tap weights, adaptive filtering parameters and, in disc drives employing magneto-resistive (MR) heads, read bias current. Such parameters are used to enable the disc drive to accommodate changes in data transfer rates that occur with respect to the radii on the discs at which the data are stored, noise levels, electrical and mechanical offsets and the like, all of which generally affect the operation of the drive.
Accordingly, the parameters are often set to an initial value during disc drive operation and then optimized against predefined acceptance criteria (for example, measured read error rate). Disc drives are often further provided with the capability of continually monitoring drive performance and adjusting certain parameters adaptively during operation to maintain optimum levels of performance.
One of the most significant variables affecting disc drive performance is temperature. Disc drives are complex electromechanical devices which include motors to rotate the discs and the actuator assembly. Although such motors are designed to operate efficiently, heat will nevertheless be generated as the disc drive operates over an extended period of time, which can substantially increase the operating temperature of the drive. Disc drives further include one or more processors and associated integrated circuitry having performance characteristics which are also affected by changes in temperature.
Attempts have been made in the prior art to monitor for variations in temperature in magnetic recording devices such as disc drives. For example, U.S. Pat. No. 6,088,662 entitled THERMOELECTRIC TEMPERATURE SENSING SYSTEM IN A COMPUTER HARD DISC DRIVE issued Jul. 11, 2000 to Flinsbaugh et al. describes a system that monitors the temperature using a temperature sensor mounted on an external circuit board and attached to the disc drive circuit board via wires.
While operable, the aforementioned and other prior art references are generally limited to the use of temperature sensors mounted on an external printed circuit board. This approach leads to a substantial discrepancy in the measured temperature compared to the actual temperature of the disc drive. Moreover, such approaches as found in the prior art typically attain temperature measurements through the implementation of additional sensors and circuitry, which generally increases the cost and complexity of the drive.
Thus, there is a continual need for improvements in the art whereby accuracy of disc drive temperature variations is needed for optimization of temperature-dependent disc drive parameters.
The present invention provides a solution to this and other problems, and offers other advantages over the prior art.
The present invention provides a method and apparatus for monitoring the temperature of a disc drive.
In accordance with one embodiment of the invention, a temperature monitoring method is provided in which the temperature value is retrieved from an internal temperature sensor. The temperature value may be used to optimnize temperature-dependent disc drive parameters.
The present invention also can be implemented as a computer-readable program storage device which tangibly embodies a program of instructions executable by a computer system to perform a temperature monitoring method.
These and various other features as well as advantages which characterize the present invention will be apparent upon reading of the following detailed description and review of the associated drawings.